Submarine groundwater discharge (SGD) is a spatially pervasive phenomenon that adds freshwater, nutrients, dissolved metals, bacteria, and other constituents to the coastal ocean. This dissertation investigated SGD-related inputs of nutrients and fecal indicator bacteria (Escherichia coli and Enterococcus sp.) to coastal waters in two Hawaiian locations, the north shore of Kaua'i and the Kona coast of Hawai'i. Concentrations of caffeine, which has been used previously as a wastewater tracer, were measured in groundwater and surface water on the north shore of Kaua'i. Both study areas have relatively light levels of urban and agricultural development, and maintaining good water quality is essential for their tourism-based economies, coral reefs, fisheries, and traditional way of life. Radium (Ra), an element with naturally elevated concentrations in coastal groundwater, was used as an SGD tracer and a mass-balance approach was used to quantify SGD. On the north shore of Kaua'i, agriculture was associated with higher nitrate + nitrite concentrations in the fresh SGD component, while phosphate and silica appeared to be controlled by geological differences in aquifer substrate. High ammonium concentrations in the fresh SGD component at one site may have been caused by a leaky cesspool. In Kona, no relation between urban development or agriculture and groundwater nutrient concentrations was observed, but bare lava rock was associated with higher nitrate + nitrite and silica concentrations in fresh SGD. Sites closer to golf courses also had higher nitrate + nitrite concentrations. Conservative estimates of total SGD on the north shore of Kaua'i ranged from 1.3 to 7.8 L per meter per minute, or up to 10% of Hanalei River discharge, and SGD contributed significant nitrate + nitrite inputs to Hanalei Bay. Estimates of SGD in Kona ranged from 5 to 1200 L per meter per minute, with between 10 and 100% of the brackish SGD comprised by the fresh SGD component. SGD-related water and nutrient fluxes on the Kona Coast -- where no rivers and streams are present -- were large compared to those reported for other sites worldwide. Caffeine concentrations in environmental waters on the north shore of Kaua'i ranged from 0-88 ng/L, on the low end of what has been reported for other locations. Metribuzin, an herbicide, was also detected at concentrations from 4-11 ng/L in five groundwater and surface water samples. A sensitivity analysis of Ra-based methods of estimating water ages and coastal mixing rates revealed that water ages shorter than 3 d cannot be estimated with confidence using Ra-based methods, even if the only uncertainty considered is analytical error. In conclusion, this dissertation provides new data about SGD and related inputs of nutrients and bacteria to Hawaiian coastal waters, suggests that even low levels of development may influence nutrient concentrations in coastal groundwater, presents the first caffeine concentrations measured in environmental water samples collected in a tropical setting, and explores the limits of applicability of Ra-based methods of estimating water ages and coastal mixing rates, providing guidance for researchers conducting Ra-based SGD studies in the future.

The study of estuaries and coasts has seen enormous growth in recent years, since changes in these areas have a large effect on the food chain, as well as on the physics and chemistry of the ocean. As the coasts and river banks around the world become more densely populated, the pressure on these ecosystems intensifies, putting a new focus on environmental, socio-economic and policy issues. Written by a team of international expert scientists, under the guidance of Chief Editors Eric Wolanski and Donald McClusky, the Treatise on Estuarine and Coastal Science, Ten Volume Set examines topics in depth, and aims to provide a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Most up-to-date reference for system-based coastal and estuarine science and management, from the inland watershed to the ocean shelf Chief editors have assembled a world-class team of volume editors and contributing authors Approach focuses on the physical, biological, chemistry, ecosystem, human, ecological and economics processes, to show how to best use multidisciplinary science to ensure earth's sustainability Provides a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Features up-to-date chapters covering a full range of topics

This book discusses how emerging groundwater risks under current and potential climate change conductions reduce available groundwater resources for domestic use, and agriculture and energy production. The topics discussed throughout this book are grouped into five sections; (i) Sea Level Rise, Climate Change, and Food Security, (ii) Emerging Contaminants, (iii) Technologies and Decision Support Systems, (iv) Surface Water-Groundwater Interactions, and (v) Economics, and Energy Production and Development. This book is unique and different from other groundwater hydrology books in that it uses a holistic approach in investigating the risks related to groundwater resources. This book will be of interest to a wide audience in academia, governmental and non-governmental organizations, and environmental entities. This book will greatly contribute to a better understanding of the emerging risks to groundwater resources and should help responsible stakeholders make informed decisions in this regard.

We have identified a need to draw together knowledge of physiochemical and biological aspects of pollution in tropical aquatic systems. This book results from this and we hope will assist in providing management strategies to protect these systems from pollution effects. In organising the book we have, as far as possible, attempted to cover the range of topics important in understanding pollution in tropical areas. Authors who are expert in their particular fields have been invited to contribute. We recognise that many topics remain uncovered but we hope will serve to assist in identifying these and stimulate interest in this area.

Over recent decades, it has become widely recognized that water exchange between coastal aquifers and the ocean is an important component of the hydrologic cycle. Twenty years have passed since Willard S. Moore (Moore, 1999) introduced the term ‘subterranean estuary’ (STE) to identify those zones within coastal aquifers where fresh groundwater mixes with surface saltwater. Like open-water estuaries, STEs regulate the transfer of chemicals to the sea under the seashore by submarine groundwater discharge (SGD). This subterranean reactive node in the land-ocean exchange pathway has a physical, even if elusive, structure created by a combination of temporally and spatially variable mass transfer across the groundwater-ocean interface and dynamic flow processes. Many case studies have shown that SGD is a key material link between coastal watersheds and the sea and indeed spatially resolved budgets of radioactive tracers in shelf waters suggest it is the dominant bulk water flux to coastal zones globally. Clearly, STE outflow as SGD is a large source of biogeochemically active solutes to shelf seas, meaning that elemental budgets for these waters have to be revised in order to account for the new input. But how? Recognizing the global prevalence and potential environmental and societal impact of SGD, numerous attempts to quantify chemical inputs into the ocean through this pathway have been published over the past 40 years. However, the role of the STE in modulating chemical fluxes to coastal waters has been generally oversimplified, making a comprehensive analysis of cause and effect relationships between SGD inputs and ecosystem dynamics merely indicative. Unfortunately, we still lack a mechanistic understanding of the processes that control the interaction between allochthonous chemical delivery and autochthonous recycling in the STE that drive compositional variability of SGD flows. Like that applied to open-water estuaries, a general practical and theoretical framework is needed – one that captures the structure and biogeochemistry of STEs and allows more accurate understanding of the chemical composition of SGD outflows, while simultaneously providing for a typological basis that provides solid support for extrapolation of local SGD chemical flux measurements to regional, and from these to global, scale. A comprehensive and critical review of the current state-of-the-art would reveal that progress requires: a) improved variable-density groundwater flow models that provide more accurate predictions and insights into the flow, salt transport, and mixing dynamics in STEs; b) quantitative understanding of the physicochemical and temporal drivers of saline groundwater seepage and composition; and c) better knowledge of the microbial ecology of STEs and links to marine, freshwater, and terrestrial drivers of STE dynamics. Significant research effort has been devoted to addressing these knowledge gaps. It is now time to provide a focused synopsis of these efforts. We propose a combination of cutting-edge original research, systematic, practice and policy reviews, methods and hypothesis and theory articles, tied together by a direction-setting perspective analysis to generate a comprehensive and accurate scientific foundation supporting environmental managers, scientists, and other stakeholders to assess SGD feedbacks on coastal ecosystem functioning and resilience and implement successful coastal management policies.

The oceans cover 70% of the Earth’s surface, and are critical components of Earth’s climate system. This new edition of Encyclopedia of Ocean Sciences, Six Volume Set summarizes the breadth of knowledge about them, providing revised, up to date entries as well coverage of new topics in the field. New and expanded sections include microbial ecology, high latitude systems and the cryosphere, climate and climate change, hydrothermal and cold seep systems. The structure of the work provides a modern presentation of the field, reflecting the input and different perspective of chemical, physical and biological oceanography, the specialized area of expertise of each of the three Editors-in-Chief. In this framework maximum attention has been devoted to making this an organic and unified reference. Represents a one-stop. organic information resource on the breadth of ocean science research Reflects the input and different perspective of chemical, physical and biological oceanography, the specialized area of expertise of each of the three Editors-in-Chief New and expanded sections include microbial ecology, high latitude systems and climate change Provides scientifically reliable information at a foundational level, making this work a resource for students as well as active researches

Dynamic Sedimentary Environments of Mangrove Coasts provides knowledge on the importance of sedimentary dynamics in managing mangrove forests. In the first part of the book, the editors seamlessly offer a general introduction of mangrove sedimentary dynamics. This leads into more in-depth information on soil surface elevation change, sea level rise, and the importance of sedimentary dynamics in the loss or gain of blue carbon. The book concludes the discussion of mangrove sedimentary dynamics by addressing the issues of climate change (e.g. sea level rise and blue carbon) on mangrove restoration and sediment.This book will assist coastal managers and academics in addressing the gaps in mangrove restoration and coastal management. As such, it will be a valuable reference for advanced undergraduate students, graduate students, researchers, academics in the field of coastal restoration, and coastal management practitioners. - Provides a state-of-the-art summary of research into sedimentary dynamics in mangrove forests - Includes updates on issues of climate change-relevant to mangroves, such as blue carbon and sea level rise - Presents scientific background and successful case studies for mangrove restoration that can solve problems relating to mangrove management